10 results on '"Zhang Yanzhen"'
Search Results
2. The optical and molecular signatures of DOM under the eutrophication status in a shallow, semi-enclosed coastal bay in southeast China.
- Author
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Zhao, Chen, Zhou, Yuping, Pang, Yu, Zhang, Yanzhen, Huang, Wei, Wang, Yuntao, and He, Ding
- Subjects
ION cyclotron resonance spectrometry ,DISSOLVED organic matter ,EUTROPHICATION ,PORE water ,WATERSHEDS ,BLACK cotton soil - Abstract
We applied stable carbon isotopes, ultraviolet-visible absorption (UV-Vis), fluorescence excitation-emission matrices spectroscopy (EEMs), and Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR-MS) to investigate the chemical composition and sources of the dissolved organic matter (DOM) in both the water column and pore water in Xiangshan Bay, a representative semi-enclosed and eutrophic bay in Zhejiang Province, China. One protein-like fluorescent component (C1) and two humic-like fluorescent components (C2 and C3) were identified by PARAFAC modeling. The concentration of dissolved organic carbon (DOC), the relative intensities of C2, C3, and black carbon-like compounds are all negatively correlated with salinity, indicating that there is a dilution effect of terrestrial signals by seawater in Xiangshan Bay. The differences in light penetration ability of Xiangshan Bay cause different degrees of photo-degradation, which may play an important role in the transformation of organic matter in Xiangshan Bay. The weak correlation between the C1 fluorescent component and salinity indicates that autochthonous sources cannot dominate the protein-like FDOM in the Xiangshan Bay drainage area. Multiple sources (such as anthropogenic inputs and release of pore water) also affect the distribution of the protein-like fluorescent component under eutrophication conditions. The relative proportion of the protein-like fluorescent component in Xiangshan Bay is on a medium level in China and anthropogenic inputs may be a significant source of DOM in coastal bays. [ABSTRACT FROM AUTHOR]
- Published
- 2021
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3. Spatiotemporal distribution and source variations of hydrocarbons in surface sediments from the Pearl River Estuary, Southern China.
- Author
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Zhang, Yanzhen, Sun, Yongge, Liu, Ben, Wang, Yuntao, Xie, Wei, Wang, Peng, Zhang, Chuanlun, and He, Ding
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ALIPHATIC hydrocarbons ,POLYCYCLIC aromatic hydrocarbons ,ALKYLBENZENE sulfonates ,RIVER sediments ,ESTUARIES ,HYDROCARBONS ,SEDIMENTS ,ENVIRONMENTAL health - Abstract
Purpose: Variations in hydrocarbon composition and concentration are essential for the assessment of its source and environmental health in estuarine environments. This study aims to reveal the spatial and temporal distribution of multiple hydrocarbons in surface sediments of the Pearl River Estuary, and to further determine various sources of these hydrocarbons. Materials and methods: Surface sediments were taken monthly from four sites along a spatial transect from the Pearl River Estuary in a whole year by using a gravitational bottom sampler. A series of bulk parameters including the grain size, total organic carbon content, and total nitrogen content were measured. Hydrocarbons in sediments were extracted and analyzed by the gas chromatography-mass spectrometry. Results and discussion: The abundances of higher plants and phytoplankton-derived n-alkanes, petrogenically derived pristane, phytane, hopanes, and steranes with geological configuration, and anthropogenically derived hydrocarbons, including linear alkylbenzenes and polycyclic aromatic hydrocarbons all showed decreasing trends towards the coastal ocean. In contrast, the diatom-derived C
25 highly branched isoprenoids increased towards saline sites. Monthly fluctuations of aliphatic and aromatic hydrocarbons at the estuarine mouth were smaller than the upstream freshwater sites, where high monthly variation (up to fivefold) was observed for most of the hydrocarbons detected. Conclusions: This study showed substantial monthly and spatial variations of hydrocarbons in the surface sediments of the Pearl River Estuary. Distribution and composition of sedimentary hydrocarbons indicate mainly anthropogenic inputs (e.g., petroleum residues and synthetic detergents) and terrestrially higher plants, followed by aquatic inputs. [ABSTRACT FROM AUTHOR]- Published
- 2021
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4. Habitat Influence on the Molecular, Carbon and Hydrogen Isotope Compositions of Leaf Wax n-Alkanes in a Subalpine Basin, Central China.
- Author
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Yan, Chaoyang, Zhang, Yiming, Zhang, Yanzhen, Zhang, Zhiqi, and Huang, Xianyu
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HYDROGEN isotopes ,CARBON isotopes ,COMPOSITION of leaves ,WAXES ,HABITATS - Abstract
Epidermal leaf waxes of terrestrial higher plants have been widely utilized for the reconstructions of paleoenvironment and paleoclimate in peat deposits. In this study, specimens of four plant species growing in both peatland and non-peatland habitats were retrieved to compare their molecular, carbon (δ
13 C) and hydrogen (δ2 H) isotopic compositions of leaf wax n-alkanes from a closed subalpine basin in Central China. Three of the four species show quite higher total concentrations of n-alkanes in the relatively dry non-peatland setting than in the peatland. In addition, the δ2 H values of long-chain n-alkanes are generally less depleted in the peatland and are comparable among different plant species, which is interpreted as the influence of inundation condition and the possible limited supply of photosynthetic products. This study reveals different patterns of plant wax molecular and isotopic compositions between peatland and the surrounding non-peatland conditions, and confirms the paleoenvironmental potential of leaf wax ratios on the peat sequences. [ABSTRACT FROM AUTHOR]- Published
- 2020
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5. The complete chloroplast genome sequence of Taxus chinensis var. mairei (Taxaceae): loss of an inverted repeat region and comparative analysis with related species.
- Author
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Zhang, Yanzhen, Ma, Ji, Yang, Bingxian, Li, Ruyi, Zhu, Wei, Sun, Lianli, Tian, Jingkui, and Zhang, Lin
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TAXUS , *CHLOROPLAST DNA , *NUCLEOTIDE sequence , *INVERTED repeats (Genetics) , *COMPARATIVE studies , *DRUG therapy - Abstract
Abstract: Taxus chinensis var. mairei (Taxaceae) is a domestic variety of yew species in local China. This plant is one of the sources for paclitaxel, which is a promising antineoplastic chemotherapy drugs during the last decade. We have sequenced the complete nucleotide sequence of the chloroplast (cp) genome of T. chinensis var. mairei. The T. chinensis var. mairei cp genome is 129,513bp in length, with 113 single copy genes and two duplicated genes (trnI-CAU, trnQ-UUG). Among the 113 single copy genes, 9 are intron-containing. Compared to other land plant cp genomes, the T. chinensis var. mairei cp genome has lost one of the large inverted repeats (IRs) found in angiosperms, fern, liverwort, and gymnosperm such as Cycas revoluta and Ginkgo biloba L. Compared to related species, the gene order of T. chinensis var. mairei has a large inversion of ~110kb including 91 genes (from rps18 to accD) with gene contents unarranged. Repeat analysis identified 48 direct and 2 inverted repeats 30bp long or longer with a sequence identity greater than 90%. Repeated short segments were found in genes rps18, rps19 and clpP. Analysis also revealed 22 simple sequence repeat (SSR) loci and almost all are composed of A or T. [Copyright &y& Elsevier]
- Published
- 2014
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6. Comparative assessment of grassland degradation dynamics in response to climate variation and human activities in China, Mongolia, Pakistan and Uzbekistan from 2000 to 2013.
- Author
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Yang, Yue, Wang, Zhaoqi, Li, Jianlong, Gang, Chencheng, Zhang, Yanzhen, Zhang, Ying, Odeh, Inakwu, and Qi, Jiaguo
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ENVIRONMENTAL degradation , *CLIMATE change , *PRIMARY productivity (Biology) , *GRASSLAND restoration , *ENVIRONMENTAL protection - Abstract
Quantifying the driving force is significant to understand the impact of climate variation and human activities on grassland degradation. In this study, we selected net primary productivity (NPP) as an indicator to quantitatively assess the relative roles of climate variation and human activities in China, Mongolia, Pakistan and Uzbekistan from 2000 to 2013. The results showed that 1.9% of grassland areas experienced degradation in Uzbekistan. By contrast, 29.6%, 16%, and 32.5% of grassland areas underwent restoration in China, Mongolia and Pakistan, respectively. Furthermore, 83.9%, 85.1%, 6.7% of restored grassland areas were influenced by climate variation and 65%, 79.1%, 11.6% of degraded areas were affected by human activities in Mongolia, Pakistan and Uzbekistan, respectively. The NPP variation also could be calculated to evaluate the impacts of these factors and results were consistent with the findings based on area. Therefore, climate variation dominated grassland restoration, human activities dominated degradation in Mongolia and Pakistan, and Uzbekistan was just the opposite. In China, 38.5% of the grassland restoration areas was caused by climate variations compared with 38% induced by human activities. On the contrary, 37.4% of grassland degradation was caused by climate variation and 30% resulted from human activities. In addition, the results based on NPP variation revealed that 39.2% of restored grassland areas were influenced by human activities and 38.2% of degraded areas were affected by climate variation. Therefore, climate variation dominated grassland degradation and the driving force of restoration was determined by the effectiveness of environmental protection programs. [ABSTRACT FROM AUTHOR]
- Published
- 2016
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7. The relationship between risk perception of COVID-19 and willingness to help: A moderated mediation model.
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Zeng, Yadi, Xiao, Gensen, Ye, Baojuan, Zhang, Yanzhen, Liu, Mingfan, Wang, Xinqiang, and Yang, Qiang
- Subjects
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COVID-19 , *PSYCHOLOGY of college students , *ATTITUDE (Psychology) , *SOCIAL alienation , *COGNITION , *RISK perception , *COMPASSION , *FACTOR analysis , *DESCRIPTIVE statistics , *EMOTION regulation - Abstract
• Risk perception of COVID-19 negatively correlated to willingness to help. • Interpersonal alienation partially mediated the link between risk perception of COVID-19 and willingness to help. • Expressive suppression moderated the associations between interpersonal alienation and willingness to help. Previous studies have revealed that situational risk factors have a significant influence on the willingness to help. Amidst the COVID-19 pandemic, maybe risk perception of COVID-19 is also correlated to the willingness to help. This study examined the mediating effect of interpersonal alienation and the moderating effect of cognitive reappraisal and expressive suppression in the relationship between risk perception of COVID-19 and willingness to help. Data from a large sample of Chinese college students (N = 2, 163) completed the measures of risk perception of COVID-19, willingness to help, interpersonal alienation, emotion regulation strategies including cognitive reappraisal and expressive suppression. The results indicated that the risk perception of COVID-19 negatively correlated to willingness to help. Interpersonal alienation partially mediated the link between risk perception of COVID-19 and willingness to help. College students' expressive suppression moderated the associations between interpersonal alienation and willingness to help. And who adopted more expressive suppression, the connection between interpersonal alienation and willingness to help was weaker compared to students who reported less expressive suppression. But cognitive reappraisal did not moderate the relationship between risk perception of COVID-19 and interpersonal alienation. Implications of the present paper for theory and practice are discussed. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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8. Comparative study of the gut microbiota in three captive Rhinopithecus species.
- Author
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Xi L, Wen X, Jia T, Han J, Qin X, Zhang Y, and Wang Z
- Subjects
- Animals, Plant Breeding, Carbohydrate Metabolism, Bacteroidetes, China, Presbytini, Colobinae genetics, Colobinae microbiology, Gastrointestinal Microbiome genetics
- Abstract
Background: Snub-nosed monkeys are highly endangered primates and their population continues to decline with the habitat fragmentation. Artificial feeding and breeding is an important auxiliary conservation strategy. Studies have shown that changes and imbalances in the gut microbiota often cause gastrointestinal problems in captive snub-nosed monkeys. Here, we compare the gut microbiota composition, diversity, and predicted metabolic function of three endangered species of snub-nosed monkeys (Rhinopithecus bieti, R. brelichi, and R. roxellana) under the same captive conditions to further our understanding of the microbiota of these endangered primates and inform captive conservation strategies. 16 S rRNA gene sequencing was performed on fecal samples from 15 individuals (R. bieti N = 5, R. brelichi N = 5, R. roxellana N = 5)., Results: The results showed that the three Rhinopithecus species shared 24.70% of their amplicon sequence variants (ASVs), indicating that the composition of the gut microbiota varied among the three Rhinopithecus species. The phyla Firmicutes and Bacteroidetes represented 69.74% and 18.45% of the core microbiota. In particular, analysis of microbiota diversity and predicted metabolic function revealed a profound impact of host species on the gut microbiota. At the genus level, significant enrichment of cellulolytic genera including Rikenellaceae RC9 gut group, Ruminococcus, Christensenellaceae R7 group, UCG 004 from Erysipelatoclostridiaceae, and UCG 002 and UCG 005 from Oscillospiraceae, and carbohydrate metabolism including propionate and butyrate metabolic pathways in the gut of R. bieti indicated that R. bieti potentially has a stronger ability to use plant fibers as energy substances. Bacteroides, unclassified Muribaculaceae, Treponema, and unclassified Eubacterium coprostanoligenes group were significantly enriched in R. brelichi. Prevotella 9, unclassified Lachnospiraceae, and unclassified UCG 010 from Oscillospirales UCG 010 were significantly enriched in R. roxellana. Among the predicted secondary metabolic pathways, the glycan biosynthesis and metabolism had significantly higher relative abundance in the gut of R. brelichi and R. roxellana than in the gut of R. bieti. The above results suggest that different Rhinopithecus species may have different strategies for carbohydrate metabolism. The Principal coordinate analysis (PCoA) and Unweighted pair-group method with arithmetic mean (UPGMA) clustering tree revealed fewer differences between the gut microbiota of R. brelichi and R. roxellana. Correspondingly, no differences were detected in the relative abundances of functional genes between the two Rhinopithecus species., Conclusion: Taken together, the study highlights that host species have an effect on the composition and function of the gut microbiota of snub-nosed monkeys. Therefore, the host species should be considered when developing nutritional strategies and investigating the effects of niche on the gut microbiota of snub-nosed monkeys., (© 2023. The Author(s).)
- Published
- 2023
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9. A randomized controlled trial of personalized text messages for smoking cessation, China.
- Author
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Lin H, Li X, Zhang Y, Wen Z, Guo Z, Yang Y, and Chang C
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- Humans, Smoking, China, Smoking Cessation, Text Messaging, Cell Phone
- Abstract
Objective: To describe a tobacco cessation intervention using personalized mobile phone text messages based on behaviour change theory and to assess why the intervention was effective., Methods: We conducted a two-arm, double-blind, randomized controlled trial in five cities in China from April to July 2021. We recruited daily or weekly smokers aged 18 years or older. The 90-day intervention was delivered using a mobile phone chat application. At different stages of quitting, intervention group participants received personalized text messages based on analyses of the strength of their intention to quit, their motivation to quit and their self-reported success at quitting. Control group participants received non-personalized text messages. The primary outcome was the biochemically verified 6-month abstinence rate. Secondary outcomes were changes in scores on the components of protection motivation theory. All analyses were by intention to treat., Findings: We randomly assigned 722 participants to intervention or control groups. Biochemically verified continuous abstinence at 6 months was 6.9% (25/360) in the intervention group and 3.0% (11/362) in the control group. Smokers who received the personalized intervention had lower scores on intrinsic rewards of smoking and response costs of quitting in the protection motivation theory analysis. These two variables were also determinants of sustained abstinence, thus explaining why the intervention group had a higher quitting rate., Conclusion: The study confirmed the psychological determinants of long-term abstinence from smoking and provided a framework to explore why such an intervention is effective. This approach may be applicable to the development or analysis of interventions targeting other health behaviours., ((c) 2023 The authors; licensee World Health Organization.)
- Published
- 2023
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10. Family Cohesion and Stress Consequences Among Chinese College Students During COVID-19 Pandemic: A Moderated Mediation Model.
- Author
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Zeng Y, Ye B, Zhang Y, and Yang Q
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- Adult, China epidemiology, Humans, Infant, SARS-CoV-2, Students, Young Adult, COVID-19, Pandemics
- Abstract
Family plays a pivotal role in individuals' mental health. During the COVID-19 epidemic, people were being quarantined at home to prevent the further spread of the virus. Therefore, the influence of family on individuals is more significant than usual. It is reasonable to assume that family cohesion can effectively alleviate the stress consequences during the COVID-19 epidemic. In the present study, a moderated mediation model was constructed to examine the mechanisms underlying the association between family cohesion and stress consequences among Chinese college students. A large sample of Chinese college students ( N = 1,254, M
age = 19.85, SDage = 1.29) participated in the study. Results indicated that family cohesion was negatively related to stress consequences. Fear of COVID-19 partially mediated the link between family cohesion and stress consequences. Excessive affective empathy reported by participants served to aggravate the relation between fear of COVID-19 and stress consequences. The study helps us understand how internal and external factors affect individual mental health that provides meaningful implications for promoting mental health., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Zeng, Ye, Zhang and Yang.)- Published
- 2021
- Full Text
- View/download PDF
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